1. Field of Invention
The present invention relates to a telecommunications network; and more particularly to a new wideband code division multiple access (WCDMA) discontinuous radio link operation mode which is intended to be used in long packet service sessions to save battery life for user equipment (UE) in a packet service mode, where the telecommunications network has not released the connection, but no data is transferred.
2. Description of Related Art
In WCDMA, the packet service session can be active for a relatively long period of time, and due to a bursty nature of transferred data there is no data flow activity between an end-user and the communications network. During this period, the UE is only performing neighbor cell measurements, and not even performing these measurements if radio conditions are stable and new commands from the network have not been received. From a user's point of view, the terminal is consuming power but not providing good performance (long service time).
In the prior art, the UE receiver is active during a whole packet connection. (In WCDMA, during a packet transfer session the UE can be in CELL-FACH and CELL-DCH states.) A mechanism to provide power saving in the UE receiver by discontinuous reception during a packet session does not exist in the prior art.
The operation time of the UE in the packet mode is fully dependent on operator radio bearer (RB) release settings (which are not specified) and how fast the connection is released after the packet transfer session.
In one case, since packet transmission can start in any frame, all slots in the frame in the downlink (DL) have to contain transport format combination indicator (TFCI) bits, the receiver (rx) has to be on during the whole frame in all frames in order to decode the TFCI, and TFCI decoding has to be performed in each frame. (Handover measurements are also assumed to be running continuously.) With the help of the TFCI, the UE detects whether the dedicated physical data channel (DPDCH) (packet) exists. If not all slots in the frame in the DL contain TFCI bits, then the UE has to use a pilot energy comparison method first to evaluate whether the DPDCH exists in the frame. In this case, all the slots only contain pilot & TFCI information only if DPDCH exists. In both of these cases, it means that the rx side has to be on and doing decoding in each slot in the frame. Thus, no rx side battery savings can be achieved during the dedicated physical control channel (DPCCH) gating.
Alternatively, in case the network is able to schedule the time instants when new packets are transferred to the UE, it is possible to signal to the UE an activity period value, which indicates the radioframe(s) the UE's have to be able to receive and decode from the network. During the same activity period, the UE is able to send measurement messages in reverse link (uplink) to the network.